Google Ads for Ecommerce: What Actually Decides Whether It Works

Shopping ads don’t run on keywords. Shopping ads (opens in new tab) use your existing Merchant Center product data, not keywords, to decide how and where to show your ads. On Shopify, that makes the product feed the targeting layer, so a product that’s disapproved, missing a required attribute, or priced differently than its landing page can’t be bid back into the auction.

The other half is measurement. Smart Bidding prices auctions from conversion data, so when the conversion signal is incomplete the effect shows up as weaker campaign performance rather than as a tracking error. Feed and measurement decide most of what people attribute to campaign structure.

Where Google and Shopify disagree, Shopify defers: the Google & YouTube channel (opens in new tab) is managed by Google.

Google gives retailers two current options. You can promote inventory with Performance Max campaigns with a Google Merchant Center feed or Shopping campaigns (opens in new tab). Both are built on the same Merchant Center product data, which is why feed work pays into either choice.

The requirements for Shopping ads (opens in new tab) are short. You need a Merchant Center account and a Google Ads account, linked. Your content has to comply with the Shopping ads policies, which are different from the Google Ads policies. And you need to be able to send Google up-to-date product data at least every 30 days.

Google sets a strict 30-day expiry policy (opens in new tab) on synced product data, and Shopify’s Google & YouTube channel refreshes products within that window to avoid suspension or data loss. If you’ve ever seen products silently drop out of Shopping, expiry is one cause to rule out.

Feed quality also does a separate job on AI surfaces, which we covered in our piece on structured data for AI search. The consequence here is narrower and harder: an attribute problem doesn’t just make a product less legible, it makes the product ineligible, and the campaign can’t bid on what it can’t serve.

Do you even need Merchant Center to run Google Ads on Shopify? No, and Shopify treats the three connections as independent. You don’t need a Merchant Center account (opens in new tab) if you only want to use Google Ads and Google Analytics, and you can connect Ads alone to set up conversion tracking for your ads without syncing products. Two preconditions apply: you need an existing Google Ads account, and the connected Google account has to be an administrator on it.

Account linking has constraints that shape how agencies and multi-store operators set things up. You can’t link a Google Ads manager account to Merchant Center (opens in new tab), a Merchant Center account can be linked to up to 500 Google Ads accounts, and a campaign can only be linked to one Merchant Center account at a time. If you unlink, campaigns that rely on that product data stop using it to serve ads.

Two settings are permanent. When you create a new Google Ads account during linking you provide your time zone and currency, and after the account is created you won’t be able to change these settings. Performance Max adds its own version of this: you can’t change the Merchant Center account (opens in new tab) after the campaign is created, and you’d have to build a new campaign to use a different one.

The Google & YouTube channel is free to install, and ad spend is billed directly to your Google Ads account (opens in new tab), with you setting the daily campaign budget. The install is easy. The side effects are where the money goes.

The most expensive one: if you already have a product feed set up, it’s overwritten (opens in new tab) to avoid conflicts between your Shopify store and your Merchant Center account. A store running a hand-built or third-party feed with custom rules, curated titles, and excluded SKUs loses that configuration when the channel syncs. Export the existing feed and document every rule before you connect anything.

Several other constraints each change a setup decision:

What happens if you tick a requirement you haven’t actually met? If you confirm requirements that aren’t met, Google can suspend your Merchant Center account. The contact-information checkbox is manual precisely because the channel can’t detect that information automatically, which makes it the easiest one to click through carelessly.

Support splits at the account boundary, and knowing that saves a day when something breaks. Shopify support can help with installing the channel and setting up products in Shopify, but Merchant Center issues, Google Ads issues, account suspensions, and ad approvals go to Google directly. Initial syncing can take up to 24 hours, and after that, product changes typically sync within a few hours.

To align with Shopify’s multi-market configurations, products in overlapping markets are separated into dedicated country data sources (opens in new tab). Because they land in a new data source with a new label using the two-letter country code, the system treats them as new items, which resets their performance history.

Campaigns that filtered products by an old data source label, such as “USD_market_1”, will no longer capture the products that moved into the new country data sources, and you have to update those campaigns to the new country code label. Campaigns targeting all products aren’t affected. Attribute rules don’t come along either: rules applied to previous data sources won’t automatically transfer.

The underlying raw product IDs, the shopify_ZZ_ values, stay unchanged, so conversion tracking continues to function normally. The break is in targeting and history, not in attribution.

Before you open a second market, list every campaign that filters by data source label and every attribute rule you’ve built, because both are things you’ll be rebuilding on the other side. The split also increases your total offer count, so a catalog near its limit may need a quota increase before the new data sources fill.

A data source has to meet a set of preconditions (opens in new tab) before it’s even sent for review: shipping settings configured at account or item level where shipping is required, a data source created for the target country, a claimed and verified URL, a verified business address, and, for the United States, tax settings at account or item level. The same list is a precondition for building a Performance Max campaign (opens in new tab) at all.

Shopify’s requirements add the store-side half. You need an online store that isn’t in private mode, a valid payment provider, and a Refund Policy and Terms of Service that must be available in your footer menu. You also need visible contact information with at least one of a mailing address, phone number, email address, or contact form, and you need to ship to a supported country in a matching currency.

The account-level rules in Google’s Merchant Center guidelines (opens in new tab) are where ordinary DTC stores trip. Products you promote have to be purchasable through your online store. You can’t promote affiliate or pay-per-click links except as a participant in a CSS program country. Users have to be able to add products to the cart and complete checkout, with at least one conventional payment method available.

Two smaller rules apply. Google says to state your return policy explicitly even if you don’t offer returns or refunds, and you process returns yourself because Google doesn’t approve or handle them. It also asks you to sign in to Merchant Center at least once every 14 months to keep the account active, which is a real failure mode for a store that set this up once and moved on.

Four different published timelines govern how long you wait, and they apply to four different things. Google gives 3 to 5 business days for new product review and 24 to 48 hours for a re-crawl after a fix, while its misrepresentation policy gives 7 business days as the typical account review (opens in new tab). Conflating them is how a merchant ends up believing a suspension appeal resolves in three days.

Warnings and disapprovals are also distinct states. Products with warnings continue to show across Google, though their performance may be limited, and unresolved warnings can lead to disapprovals, while disapproved products stop showing entirely. Preemptive item disapproval is a third state: when price or availability don’t match between your product data and your landing pages, Google disapproves products likely to violate requirements, and a review is required to clear it.

Most disapprovals trace to the website rather than the feed, and Google lists the causes. Placeholder content, broken links, missing or inconsistent information, inaccurate product descriptions, mismatched categories between site and product data, a robots.txt blocking Googlebot or Googlebot-image, landing pages that are unavailable through server errors or slow loading, and landing pages that redirect to a generic page instead of the specific product.

For account-level violations, Google sends a warning email and gives you 7 or 28 calendar days to fix the issue, but it may not issue a warning for egregious violations. In some cases an egregious account-level issue results in immediate suspension with no warning at all. Merchants on a third-party platform may be able to request a review directly through that application, which is the route a Shopify merchant takes from inside the channel.

Which suspension policy should a Shopify store read first? Misrepresentation, because Google scopes that policy to Shopping ads and local inventory ads rather than to all of Google Ads, and because its consequences are the harshest published. Google calls violations “egregious,” says accounts will be suspended “upon detection and without prior warning,” and says accounts are only reinstated “in compelling circumstances.” The omissions it lists as violations are mundane: missing merchant terms and conditions or shipping information, and a return and refund policy that’s unclear, missing, or not easily discoverable.

Two procedural warnings change how you should respond to a suspension. Google says that before submitting a bulk appeal you must remove policy-violating items, because a bulk appeal across a large set of offers “risks immediate failure if violations are found,” which may limit your ability to appeal those products again. And it says not to delete a suspended account and create a new one, since the new account is likely to be flagged as well.

Google defines its own tiers for product data attributes (opens in new tab), and its Required definition is the operative one: “Submit this attribute. If you don’t, your product won’t be able to serve in ads and free listings.” It’s the difference between a feed that’s merely imperfect and one that’s ineligible.

The universally required set is small. An id capped at 50 characters, which Google says should use the product’s SKU where possible and should stay the same across updates. A title capped at 150 characters and a description capped at 5,000. A link on your verified domain, an image_link, an availability value from in_stock, out_of_stock, preorder, or backorder, and a price.

Price rules cause avoidable disapprovals on Shopify stores that run memberships or subscriptions. Google says not to submit a price of 0 outside the narrow cases of mobile devices sold with a contract and physical goods sold with a subscription, and that any customer must be able to buy at the submitted price “without having to sign up for a membership program (free or paid).” For the US and Canada, don’t include sales tax, GST, VAT, or import tax in price; for all other countries, include VAT or GST.

Identifiers have an asymmetric penalty. Products that have a GTIN but are submitted without one may have limited visibility, while a product submitted with an incorrect GTIN will be disapproved. Google’s instruction is to only provide a GTIN if you’re sure it’s correct (opens in new tab), not to guess, and not to submit one for a product that doesn’t have one, which is the normal case for store brands and single-seller products.

The identifier_exists attribute defaults to yes if you don’t submit it, and setting it to no when the product does have identifiers may get the product disapproved. Variants need their own unique identifiers: if a product comes in multiple colors or sizes, each variant needs a different unique identifier, and Google prohibits submitting multiple products for the same country and language that share a GTIN and have identical variant attribute values. GTIN format is 0, 8, 12, 13, or 14 digits, repeatable up to 10 times.

Google contradicts itself on one detail, so treat it as unsettled rather than resolved. Its GTIN attribute rules give coupons the GS1 prefix ranges “05, 98 or 99”, while its product data specification gives a coupon the GS1 prefix ranges “98 – 99”. If your catalog is anywhere near that edge, validate against the GTIN attribute rules and expect the specification to disagree.

Availability is the attribute most likely to break quietly as inventory moves. Google requires availability to be consistent (opens in new tab) across the landing page, structured data (if available), checkout page, and your data source, and a mismatch in one of these will trigger a product disapproval. For in-stock offers the buy button has to be active, and for preorder or backorder items the page has to display the expected shipping date.

Google also distinguishes preorder from backorder in a way many feeds get backwards: preorder is only for new products that haven’t been released yet, while existing products that are out of stock and will return should use backorder. For temporary removals, Google says to use the pause attribute to stop a product showing for up to 14 days, and to use excluded_destination rather than setting products to out of stock when you take the site down for maintenance or a holiday. It warns explicitly against deleting items, because adding an offer back after deletion will take a significant amount of time before it can show again.

Images carry a requirement with a date on it. Google’s new image size requirements (opens in new tab) are at least 500 by 500 pixels for all products beginning January 31, 2027, and Google recommends 1500 by 1500 or above for best performance across listing formats. Hard limits are 64 megapixels and 16MB per file.

Re-crawl behavior changes how you should ship new photography. A new unique image URL prompts a faster recrawl, typically within 3 days (24-72 hours), while reusing the same URL can take significantly longer (up to 6 weeks). That’s roughly a fourteenfold difference, and the fix is free: change the filename rather than overwriting the asset in place.

Promotional overlays remain a common disapproval cause, and Google’s banned list is specific: calls to action like “buy”, service information such as extended warranty or free shipping, price information, promotional adjectives like best or cheap, condition or compatibility claims, watermarks, brand names, logos that aren’t an inherent part of the product, and barcodes. Borders are out too. Google’s framing advice, which it labels as advice rather than requirement, is to frame the product at no less than 75% and no more than 90% of the image space on a solid white or transparent background.

Free listings (opens in new tab) are a separate program with their own requirements, and the feature is turned on by default for you in most cases. Products can appear on Google Search, Google Maps, Gemini, YouTube, the Shopping tab, Google Images, and Google Lens. Shipping settings or the shipping attribute are required in a named country list that includes the US, UK, Canada, Australia, and most of the EU.

Two requirement sets diverge in a way that’s easy to get backwards. item_group_id is required in Brazil, France, Germany, Japan, the UK, and the US if the product is a variant, and separately required for free listings for all product variants, with no country scoping. The four apparel attributes, color, size for clothing and shoes, age_group, and gender, follow the same pattern: they’re needed to show Apparel & Accessories products in free listings, and to show them in Shopping ads targeting those same six named countries.

The practical read is that free listings are the stricter of the two on variant and apparel data. A store selling apparel outside those six countries can be fully eligible for Shopping ads while its variants stay ineligible for free listings, which looks like an unexplained visibility gap if you’re only watching the ads account.

A Shopify-specific control decides what actually lands in your feed’s title field. You can either sync your product titles and descriptions or use the title tag and meta description from the search engine listing. Google’s reason for the second option is that you might want the search listing versions so you can include more keywords for search engine optimization on Google Shopping without changing product information in your store. The control sits in the Google & YouTube app under Settings, then the Product feed section, then “Additional settings to sync with Google Merchant Center” under Product sync, then “Product titles and descriptions.”

Title rules (opens in new tab) split cleanly into requirements and advice, and Google marks the line itself. Google’s line on the minimum requirements is “If you don’t follow these requirements, we’ll disapprove your product.” It requires accurate titles matching the landing page, variant differentiation, no promotional text including price, sale dates, shipping, delivery dates, or your company name, and no capital letters for emphasis. The capitalization fix is GREEN SHIRT becoming Green shirt.

The best practices are labeled as best practices, which is how they should be weighted. Google suggests using all 150 characters, putting the most important details first because users will usually notice only the first 70 or fewer characters of your title, depending on screen size, and using keywords. If a title exceeds the limit Google truncates it and sends a warning that it did.

If you’re using structured attributes, precedence matters: when both structured_title and title are provided, Google only uses the title attribute. AI-generated titles have their own path, requiring structured_title with a digital_source_type of trained_algorithmic_media.

Google may also rewrite your title in the ad. It may promote key product attributes using content from your landing page, images, and other signals. In Google’s example, a query for “King size mattress” turns a merchant title beginning “Memory foam medium firm mattress king” into a dynamic title beginning “King – Memory foam medium firm.” An opt-out exists through your account manager or support, with requests typically processed in 3 to 5 business days.

Product status in the Shopify app tells you where each product stands, using four values: Not approved, Limited, Under review, and Approved. Limited means only some products are syncing because of errors or missing product data. A store sitting at Limited for weeks should start with the troubleshooting set Shopify names: missing description, missing image, unavailable landing page, missing GTIN or MPN, promotional overlay on image, and excessive capitalization.

Performance Max campaigns replace Smart Shopping (opens in new tab). Existing Smart Shopping campaigns were automatically upgraded, and you can no longer create Smart Shopping campaigns. Any decision framed as Smart Shopping versus PMax is a decision about a campaign type you can’t create.

Standard Shopping, by contrast, is alive. Google presents it beside Performance Max as a current option, and the differences in the table below are the real decision inputs.

One row in that table answers the question of why anyone still runs Standard Shopping: Manual CPC appears under Shopping campaigns and not under Performance Max. If you need to set the price of a click yourself, that points you to Shopping campaigns.

Performance Max (opens in new tab) is a goal-based campaign type that accesses all Google Ads inventory, including YouTube, Display, Search, Discover, Gmail, and Maps, from one campaign. You can create one when your objective is Sales, Leads, Website traffic, or Local store visits and promotions, or with no goal guidance. Its campaign-level controls are keywordless targeting, Final URL expansion or asset optimization, search themes, negative keywords, and brand exclusions.

Search campaigns containing an exact match keyword are prioritized to serve over Performance Max when a query hits an exact match keyword, and search themes carry the same priority as phrase and broad match keywords. One condition reverses the outcome: if your Search campaign is budget-limited, Performance Max may occasionally serve on exact match terms.

That turns an underfunded Search campaign into a PMax targeting decision you didn’t make. If you run both and your brand or highest-intent Search campaign is capped, PMax can pick up those exact match queries. Funding the Search campaign is the control, not a PMax setting.

Search themes and brand exclusions are the two levers worth learning properly. You can add up to 50 search themes (opens in new tab) per asset group, and Google describes them as a broader signal to its AI rather than as keywords. Brand exclusions (opens in new tab) apply to both Search and Shopping ads within PMax, block misspellings and related subsidiary brands automatically, and, usefully, can be configured to let Shopping ads keep serving on those excluded brand terms.

Final URL expansion moves a decision from you to Google. With expansion on, Google may replace your Final URL with a more relevant landing page and generate a matching dynamic headline and description. Google is explicit about who stays responsible: “you remain responsible for reviewing and ensuring compliance and accuracy of landing page content, and all dynamically generated assets.” One more constraint: text customization can’t be applied to Shopping Ads.

On cost, Performance Max has no startup costs (opens in new tab) and you pay for performance, with billing that varies by surface. YouTube instream is billed on CPM, while Search, Shopping, and Display are billed on clicks.

A single campaign therefore mixes several billing bases, not one. Beyond CPM and clicks, Google bills a Gmail teaser click to expand the ad as an “engagement” and charges Promoted Pins on Maps by views when you’re bidding to store visits or store sales. Compare its cost per click to a Shopping campaign’s and you’re comparing across all of those bases at once.

Performance Max has a search terms report, and it has had one for years. The PMax search terms report (opens in new tab) shows the search terms that triggered your ads, and lives under the Campaigns menu as “Search terms and landing pages for Performance Max.” Data in that report starts from March 2023, and data prior to that date isn’t shown.

Segmentation is what makes the report usable for a retailer. You can use “Ad format” segmentation to see the ad type served for each search term, differentiating between Shopping ads and text ads, which helps analyze format-level brand exclusions. The report includes terms that don’t lead to conversions, so it isn’t a converted-queries-only view. Store visits and store sales conversions aren’t available in it.

Coverage has a caveat, and its subject matters. In the search terms report generally (opens in new tab), some search terms without enough query activity are omitted to meet Google’s data privacy standards. Treat low-volume suppression as a property of the report you’re viewing rather than as a PMax-specific rule Google has published.

Acting on what you find takes two different routes. To stop serving for a keyword on Search and Shopping inventory you apply negative keywords at account or campaign level, while Display and Video inventory requires excluded content keywords in the Content Suitability center. One exclusion list doesn’t cover the campaign.

The accurate criticism of PMax reporting is about placements, and Google makes it itself. Google says placement reports (opens in new tab) shouldn’t be used to evaluate performance, as information on the placement report doesn’t include performance from all channels, and that they should be used as a brand safety tool. The structural reason is that Search isn’t considered a placement, and is excluded from any placement reporting.

The report carries two more limits. Google Owned & Operated is a single bucket combining impressions from some YouTube formats, Discover, Feed, Gmail, and other Google properties, and “Anonymous.google” covers placements where publishers have chosen not to disclose their site name. Google frames the report around where ads served and how many impressions they received. Google’s instruction is to use placement reports for brand safety, not performance evaluation.

Asset group reporting (opens in new tab) has a similar shape, with a warning against the obvious instinct. A Combinations report lists the 6 best combinations per asset category across 18 tiles for text, image, and video. Google says asset groups with higher CPA or lower ROAS still contribute to achieving your campaign goals, and it doesn’t recommend removing asset groups based on this information.

There’s also a math caveat. Conversions aren’t split across multiple components of an ad, so the number of conversions across all assets won’t equal total conversions for the campaign. Asset-level conversion numbers aren’t additive, and treating them as a budget allocation view produces a wrong answer.

PMax exposes search terms back to March 2023, ad format segmentation, asset and asset group performance, channel performance, and a placement report Google says is for brand safety. Placement reporting doesn’t cover Search. Google’s stated instruction is to evaluate at the campaign level because the system optimizes across channels against your conversion objectives.

Shopify’s current mechanism is the pixels manager (opens in new tab), with two paths: app pixels installed through marketing and data collection apps, and custom pixels added by a developer in the pixels manager. Pixels automatically load on the Storefront, Checkout, Thank you page, and Order status page. Customer account pages are the exception, loading pixels only after you connect a custom subdomain, and tracking only the page_viewed event there.

That’s the steady state after the Additional Scripts field went away for non-Plus stores, which we wrote about when Shopify’s Additional Scripts sunset broke conversion tracking. What ended was the script field, not conversion measurement on checkout pages.

The sandbox is where paid media implementations still hit walls. Pixels sandboxes can’t render user interface elements like buttons, forms, banners, or modals, and these can’t be detected: events, metadata, and user information such as email and phone from DOM scraping, outbound link clicks from DOM scraping, page scrolling, and click and mouse-movement heatmaps. Automatic detection of page URLs in the Lax sandbox includes a sandbox version that may not exactly reflect the main window’s URL.

For conversion pixels specifically, Shopify says standard checkout events and customer actions work for most conversion tracking, that features which automatically scrape forms for email addresses or phone numbers might not work in the sandbox, and that most pixel providers support passing that data manually instead. Running Google Tag Manager doesn’t route around this: GTM can run as a custom pixel, but pixels it loads still run within the sandbox with the same limitations.

Google’s enhanced conversions (opens in new tab) works by sending hashed first-party data, using hex SHA256 on customer data such as email addresses before it reaches Google. Normalization is specified: strip leading and trailing whitespace, lowercase the text, format phone numbers to E.164, and remove periods preceding the domain in gmail.com and googlemail.com addresses. Enhanced conversions for web (opens in new tab) changed in 2026: web and leads are now a single on/off setting, and from April 2026 Google accepts user-provided data from website tags, Data Manager, and API connections, with existing users migrated automatically.

DOM scraping for email and phone doesn’t work in Shopify’s sandbox, and providers support passing the data manually. Enhanced conversions needs user-provided data such as a hashed email. Treat how user-provided data reaches the tag on your store as an implementation question to answer during setup rather than as a requirement either vendor has written down.

Conversion configuration (opens in new tab) has three details that quietly decide bidding quality. Google calls configuring conversion actions as primary or secondary critical, since primary actions are the biddable ones. An Unverified or Inactive status is normal for new tags until the first conversion or test event is recorded. And view-through conversions are excluded from the main Conversions column so Smart Bidding optimizes for active interactions.

For your conversion data source, Google says Google Analytics is the most efficient choice if you already use it and want to reuse existing event tracking, and it recommends the Google tag if you don’t use Analytics or if you need Ads-specific features like enhanced conversions. If you import from Analytics, expect a wait: it can take 24 to 48 hours after linking or marking key events before import options appear in Google Ads.

Consent shapes all of this in the EEA and UK, and each vendor handles its own half. Consent mode (opens in new tab) doesn’t provide a banner, it interacts with yours. In basic mode, tags don’t load until interaction and no data including consent status is transferred on refusal, while in advanced mode, tags load and send cookieless pings while consent is denied. Advanced mode uses an advertiser-specific model rather than a general one, and Google says after at least 7 full days of implementation there may be enough data to report uplift.

Shopify’s half is its customer privacy settings (opens in new tab) and the consent gate in the pixels manager. In markets configured to require consent, usually the EEA and UK, web pixels run only when visitors have given the required permissions, with new pixels defaulting to requiring Marketing and Analytics permissions. Where a cookie banner is active, data is collected only after consent, so there might be a reduction in the amount of data available for analytics, marketing, and personalization. That’s observable through decreased session counts and other metrics that rely on session data, including conversion rates.

Shopify’s gate decides whether a pixel runs at all. Event data sent to Google from customers in the EEA won’t be used for personalized advertising unless Consent Mode v2 is activated and valid consent is obtained.

A Shopify cookie banner can capture that consent, a third-party banner has to be integrated with Shopify’s customer privacy settings, and a custom web pixel needs a code snippet inserted manually to activate Consent Mode v2. That last case is the one to check, because it’s the only one where nothing happens by itself. One more gate sits on the same mechanism: pixels configured as data sale won’t run for customers who have opted out of data sales or sharing, unless the pixel supports limited data use.

Google publishes conversion thresholds for Target ROAS eligibility (opens in new tab), and the list is specific. Search and Shopping campaigns need at least 15 conversions in the past 30 days at the conversion tracking level, Display needs at least 15 conversions with valid values across all campaigns combined, and App campaigns need at least 10 conversions daily or 300 in 30 days.

The rest of the list runs: Demand Gen needs at least 50 conversions in the past 35 days with 10 of them in the past 7 at campaign level, or 100 in 35 days across all Demand Gen campaigns in the account; Video Action needs at least 30 in the past 30 days; Hotel campaigns need 50 per week at campaign level; and Travel needs 50 in the past 7 days at campaign level. Conversions must have a value greater than zero to count. Note the unit differences, because Search and Shopping are measured at the conversion tracking level while several others are scoped to the campaign.

Performance Max isn’t on that list. Portfolio bid strategies aren’t available for PMax and average target ROAS reporting is supported, but that list doesn’t assign PMax a conversion threshold. So there’s no published Target ROAS conversion minimum for Performance Max to quote, and any figure you’ve been given for one didn’t come from that list.

Is there a minimum daily budget for any of this? Not one that Google publishes. Google states no minimum daily spend for Shopping, PMax, or Demand Gen campaigns. The closest published guidance is the budget panel Google puts on the Performance Max and Demand Gen campaign review pages, which displays up to 3 daily budget suggestions labeled Low, Medium, and High, based on your campaign settings and account history, with the lowest being the minimum recommended budget for that campaign.

A brand-new account has no account history for the suggestion to draw on, and Google doesn’t say what the recommendation falls back to in that case. Treat the Low figure as a system output rather than a published floor.

One budget-to-target ratio exists, scoped to a single campaign type. For Demand Gen campaigns (opens in new tab) using target CPA bidding, Google recommends a budget at least 10 times your target CPA. That’s Demand Gen guidance. Transplanting it onto Performance Max or Shopping produces a number Google has never published for those campaign types.

At a $30 target CPA, 10x means a $300 daily budget, and using Google’s own monthly multiplier below, that’s roughly $9,120 in a month. That total is arithmetic on Google’s published figures, not a Google-published total.

Google does publish the spend mechanics: you’ll never pay more than two times your average daily budget (opens in new tab) on a given day, or 30.4 times your average daily budget in a month, which Google scopes to most campaigns rather than to all of them. Google’s own worked example divides 304 by 30.4 to give $10 per day.

Applying those multipliers, a $50 daily budget can spend up to $100 on a single day and up to $1,520 across a month, which is the number to bring to a finance conversation rather than $1,500. For Target ROAS, Google makes the same point as advice, recommending you be comfortable spending up to twice your average daily budget.

Google publishes two learning numbers and they measure different things. Smart Bidding strategies require a standard 7-14 day learning phase, and Google warns against frequent manual changes to budgets, targets, or conversion goals during it, because those adjustments reset the learning window. The learning period (opens in new tab) has a data threshold instead: up to around 50 conversion events or 3 conversion cycles for the bid strategy to calibrate, faster when more conversion data is present. One is a duration and one is a volume, so a campaign can satisfy the first and still be short of the second.

A store sitting exactly at the Search and Shopping eligibility floor of 15 conversions in 30 days would take roughly 100 days to accumulate 50 conversion events, which is arithmetic on Google’s two thresholds rather than a rule Google states. Eligibility for a bid strategy and having enough data for it to calibrate are not the same milestone.

Google names three things that put a strategy into Learning (opens in new tab): a new strategy, a setting change, and a composition change where campaigns, ad groups, or keywords move in or out. Google’s advice is to keep using the account normally while being mindful that metrics vary. A fourth trigger is that ad group target changes may trigger Learning on Shopping campaigns, and Google says its algorithms continue to learn even when the bidding status no longer shows Learning. The learning period isn’t applicable to Manual CPC.

Separately, Google publishes guidance on the window you should judge results over, and it isn’t an eligibility rule. For Smart Bidding (opens in new tab), Google recommends measuring performance over periods with at least 30 conversions, or 50 for Target ROAS. For Target ROAS, Google adds that you should report values across relevant campaigns for 4 weeks or 1 to 2 conversion cycles, whichever is longer, before setting a target, and that performance generally improves with fewer, larger campaigns.

One dated change is worth ruling in or out before you rebuild anything. Google set August 17, 2026 as the start of an update to its bidding systems for campaigns that are limited by budget, which Google says is to deliver more consistent and predictable performance. If your campaigns use Target CPA or Target ROAS, Google says these changes may cause temporary performance and traffic fluctuations.

A Bid Target Adjustment Tool is available starting July 6, 2026, and Google set June 2026 as the start of a relabeling of its strategies, with “Maximize conversions with a Target CPA” becoming “Target CPA” and the ROAS equivalent becoming “Target ROAS,” while the underlying behavior stays the same.

Budget-limited describes a lot of small Shopify advertisers. If performance moved in late August without a corresponding change on your side, that’s a cause to check before you start attributing it to creative fatigue or seasonality.

For Shopping ads, Performance Max, Demand Gen, Merchant Center, and free listings, Google publishes no click share, no average ROAS, no CTR, no conversion rate, and no PMax-versus-Shopping performance comparison. The quantities Google does publish about outcomes are spend mechanics, bid strategy eligibility thresholds, and learning thresholds.

The one other category of number is reach marketing about its own surfaces, and it arrives without methodology. Google claims Demand Gen “lets you reach more than 3 billion active monthly users with more than 50 billion global daily views on Shorts alone,” which is a vendor figure with no stated measurement basis. It tells you about inventory scale and nothing about what your account should expect.

So any ecommerce benchmark you’re handed came from someone’s case study, panel, or aggregated client data rather than from Google. That doesn’t make those figures worthless, but it does mean they carry a sample you can’t inspect, and they can’t settle a question about your catalog, your margins, or your market. Your comparison set is your own account history. Record a clean baseline before you change campaign structure, not after.

Most of these steps gate the ones after them, so the order is fixed.

We build and run these stacks in-house, feed through campaign through measurement, which is why the feed work and the ads work don’t sit with different teams here. If you want to know which of the steps above is actually costing you, our Google Shopping and Performance Max management work starts where yours is breaking rather than with a rebuild you didn’t ask for.

You built products worth finding. Get a free Growth Audit of your Google Ads and feed setup and see exactly why they aren’t being seen, and what it takes to fix it.

A clear look at what’s in your way.